The present invention relates to a method of driving a solid-state image sensor and a solid-state imaging apparatus using a solid-state image sensor and, more particularly, to a method of driving a solid-state image sensor and a solid-state imaging apparatus attaining an electronic zooming function or an image stabilizing function (such functions are realized by generating a video signal from charges stored in pixels at a portion of the whole of an entire effective pixel area of the solid-state image sensor).
With the spread of video cameras in recent years, demands from users for functions of the cameras have become diversified. At the same time, with the progress of the semiconductor technologies and the increase in packaging density of devices on substrates, video cameras are becoming more and more smaller in size and lighter in weight.
As one of the functions of video cameras, there is a zooming function. In the past, the zooming function was realized by the use of a zooming-lens formed of a plurality of lenses in combination provided with a complex cam mechanism. When zooming of a higher power was demanded from such cameras by users, it was met by increasing the number of lenses. By such arrangement, however, the portion of the video camera occupied by the lenses increases, and it goes against the objective to develop video cameras of smaller size and lighter weight.
To overcome the above described difficulties, there is proposed an electronic zooming function, as disclosed in Japanese Patent Application Laid-Open No. 1-228280 and the like, in which the method for driving a solid-state image sensor is adapted such that the driving pulse of the solid-state image sensor is controlled to provide an increased number of pulses during one horizontal scanning period (hereinafter called 1H) and vertical CCDs of the solid-state image sensor are thereby quickly transferred, and thus a zooming function is performed without increasing the number of lenses.
As the camera becomes smaller in size, an image swing becomes liable to occur. When the camera was swung by a swing of the operator's hands supporting the camera, the image will unpleasantly swing when the shot image is reproduced.
To compensate for such image swing, there is proposed a method disclosed for example in a paper "Electronic Image Stabilizer for Video Camera Use" by Kinugasa et al., IEEE Trans. on. C. E., Vol. 36, No. 3, August 1990, pp. 520-525, in which method a detector for detecting an image swing is provided in a video camera and a pulse signal output from a driver for driving a solid-state image sensor is controlled by the detection output signal from the detector to change the position of the scanning pixel area within the effective pixel area to such an extent that a camera swing is canceled and thereby the image swing is compensated for.